Other Sources of Atmospheric Mercury

“The Global Atmospheric Mercury Assessment - Sources, Emissions, and Transport” by the United Nations Environment Programme (UNEP), December 2008. This document provides a comprehensive overview of atmospheric mercury emissions. It describes sources of atmospheric mercury emissions and models transport/deposition geographically. This paper explains that natural sources of mercury such as rock erosion, volcano eruptions, and forest fires account for one-third to one half of mercury emissions to the atmosphere. Of the anthropogenic sources (caused by humans), the paper explains that coal-burning is the largest anthropogenic source of mercury emissions in the atmosphere.

In Halting the Child Brain Drain - Why we need to tackle global mercury contamination by the ‘Stay Healthy! Stop Mercury’ campaign, December 2006, page 24 provides information on the sources of mercury emissions in Europe. This document provides a good overview of the main sources of environmental mercury exposure and related health outcomes from a European perspective.

Notable sources of mercury emissions caused by humans include:

  • Cement production – cement kilns burn coal to create the high temperatures necessary to produce cement. Some cement kilns also burn industrial natural gas, which emits a small amount of mercury (domestically used natural gas has had the mercury scrubbed out before burning). Additionally, mercury emissions may originate from the limestone being processed and also from fly ash, if that is being added. After years of efforts from organizations like Earth Justice, the EPA proposed new regulations on 4/21/09 that will slash mercury emissions from cement kilns.

  • Incineration of mercury-containing products in medical waste – historically, many medical testing devices have utilized mercury. Health Care Without Harm has partnered with the World Health Organization (WHO) to replace mercury-based medical devices with safer, non-mercury alternatives. The initiative, announced on 12/05/08, aims to replace at least 70% of all mercury thermometers and blood pressure devices around the world within the decade.

  • Incineration of mercury-containing products in municipal waste – mercury-containing ‘button” batteries, fluorescent lightbulbs, Compact Fluorescent Lightbulbs (CFLs), and many other products end up in municipal waste dumps despite regulations that such products should be disposed of as hazardous waste. When municipal waste is incinerated as a means of disposal or as a means to generate electricity, the mercury is vaporized and released into the atmosphere.

  • Gold mining, industrial scale – ore containing gold also contains a significant amount of mercury. The industrial-scale processing of gold ore is a large source of mercury emissions. Gold mines need mercury-emissions controls to meet regulatory requirements.  See 6/1/09 article Nevada gold mine closed due to mercury emissions. 

  • Small-scale artisanal gold mining – in small-scale illegal gold mining operations, mercury is used to amalgamate with gold in the ore. Then the mercury is heated and evaporated off, leaving the gold. The miners are typically poor, have few resources to invest in pollution-control devices, and perhaps have little awareness of the hazards of mercury despite having experienced neurological and other effects. Per the UNEP report previously referenced, an estimated 10-15 million people in 55 countries are engaged in artisanal/small-scale gold mining, producing 20-30% of the world’s gold, with another 85-90 million people indirectly dependent upon this activity.

  • Burning of other fossil fuels such as natural gas and gasoline – gasoline, diesel, and other petroleum products contain a small amount of mercury, but are not considered to be major source of atmospheric mercury. Natural gas contains some mercury when first captured (more than gasoline, but less than coal). However, much of the mercury is removed during processing of the natural gas prior to its transmission through pipelines for use by industrial or residential customers.

  • Crematorium – the cremation of a human body results in mercury emissions, primarily from dental amalgams and secondarily from other mercury deposited in the body.

  • Forest Fires – forest fires, whether caused by man or nature, vaporize mercury that has been deposited on the plants and soil from the atmosphere.

More details on Other Sources of Atmospheric Mercury:

Cement Kiln Mercury Emissions Regulated – In Time For Earth Day– 4/22/09

EPA Proposal Targets Mercury in Cement Kilns – 4/21/09

Global Alliance for Incinerator Alternatives / Global Anti-Incinerator Alliance (GAIA) is a worldwide alliance of more than 600 grassroots groups, non-governmental organizations, and individuals in over 80 countries whose ultimate vision is a just, toxic-free world without incineration. GAIA work against incinerators and for safe, sustainable and just alternatives.